/*
 * Copyright (C) 2008 ZXing authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.zxing.view;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.Typeface;
import android.util.AttributeSet;
import android.view.View;

import com.google.zxing.ResultPoint;
import com.google.zxing.camera.CameraManager;

import java.util.Collection;
import java.util.HashSet;

/**
 * This view is overlaid on top of the camera preview. It adds the viewfinder
 * rectangle and partial transparency outside it, as well as the laser scanner
 * animation and result points.
 */
public final class ViewfinderView extends View {
    /**
     * 刷新界面的时间
     */
    private static final long ANIMATION_DELAY = 10L;
    private static final int OPAQUE = 0xFF;

    /**
     * 四个绿色边角对应的长度
     */
    private int ScreenRate;

    /**
     * 四个绿色边角对应的宽度
     */
    private static final int CORNER_WIDTH = 5;

    /**
     * 手机的屏幕密度
     */
    private static float density;
    /**
     * 字体大小
     */
    private static final int TEXT_SIZE = 16;
    /**
     * 字体距离扫描框下面的距离
     */
    private static final int TEXT_PADDING_TOP = 30;

    /**
     * 画笔对象的引用
     */
    private Paint paint;

    /**
     * 将扫描的二维码拍下来，这里没有这个功能，暂时不考虑
     */
    private Bitmap resultBitmap;
    private Collection<ResultPoint> possibleResultPoints;
    boolean isFirst;

    int borderColors[] = {Color.parseColor("#ff99cc00"), Color.parseColor("#ffff4444"), Color.parseColor("#ff33b5e5"), Color.parseColor("#ffaa66cc")};

    public ViewfinderView(Context context, AttributeSet attrs) {
        super(context, attrs);

        density = context.getResources().getDisplayMetrics().density;
        //将像素转换成dp
        ScreenRate = (int) (60 * density);

        paint = new Paint();

        possibleResultPoints = new HashSet<ResultPoint>(5);
    }

    @Override
    public void onDraw(Canvas canvas) {
        //中间的扫描框，你要修改扫描框的大小，去CameraManager里面修改
        Rect frame = CameraManager.get().getFramingRect();
        if (frame == null) {
            return;
        }

        //获取屏幕的宽和高
        int width = canvas.getWidth();

        //paint.setColor(resultBitmap != null ? resultColor : maskColor);

        //画出扫描框外面的阴影部分，共四个部分，扫描框的上面到屏幕上面，扫描框的下面到屏幕下面
        //扫描框的左边面到屏幕左边，扫描框的右边到屏幕右边
//		paint.setColor(maskColor);
//		canvas.drawRect(0, 0, width, frame.top, paint);
//		canvas.drawRect(0, frame.top, frame.left, frame.bottom, paint);
//		canvas.drawRect(frame.right, frame.top, width, frame.bottom,paint);
//		canvas.drawRect(0, frame.bottom , width, height, paint);

        if (resultBitmap != null) {
            // Draw the opaque result bitmap over the scanning rectangle
            paint.setAlpha(OPAQUE);
            canvas.drawBitmap(resultBitmap, frame.left, frame.top, paint);
        } else {

            //画扫描框边上的角，总共8个部分
            paint.setColor(borderColors[0]);
            canvas.drawRect(frame.left, frame.top, frame.left + ScreenRate, frame.top + CORNER_WIDTH, paint);
            canvas.drawRect(frame.left, frame.top, frame.left + CORNER_WIDTH, frame.top + ScreenRate, paint);

            paint.setColor(borderColors[1]);
            canvas.drawRect(frame.right - ScreenRate, frame.top, frame.right, frame.top + CORNER_WIDTH, paint);
            canvas.drawRect(frame.right - CORNER_WIDTH, frame.top, frame.right, frame.top + ScreenRate, paint);

            paint.setColor(borderColors[2]);
            canvas.drawRect(frame.left, frame.bottom - CORNER_WIDTH, frame.left + ScreenRate, frame.bottom, paint);
            canvas.drawRect(frame.left, frame.bottom - ScreenRate, frame.left + CORNER_WIDTH, frame.bottom, paint);

            paint.setColor(borderColors[3]);
            canvas.drawRect(frame.right - ScreenRate, frame.bottom - CORNER_WIDTH, frame.right, frame.bottom, paint);
            canvas.drawRect(frame.right - CORNER_WIDTH, frame.bottom - ScreenRate, frame.right, frame.bottom, paint);

            //画扫描框下面的字
            paint.setColor(Color.WHITE);
            paint.setTextSize(TEXT_SIZE * density);
            paint.setAlpha(0x40);
            paint.setTypeface(Typeface.create("System", Typeface.BOLD));
            paint.setTextAlign(Paint.Align.CENTER);
            canvas.drawText("请将条形码/二维码置于取景框内", width / 2, (float) (frame.bottom + (float) TEXT_PADDING_TOP * density), paint);

            Collection<ResultPoint> currentPossible = possibleResultPoints;
            if (currentPossible.isEmpty()) {
            }

            //只刷新扫描框的内容，其他地方不刷新
            postInvalidateDelayed(ANIMATION_DELAY, frame.left, frame.top, frame.right, frame.bottom);

        }
    }

    public void drawViewfinder() {
        resultBitmap = null;
        invalidate();
    }

    /**
     * Draw a bitmap with the result points highlighted instead of the live
     * scanning display.
     *
     * @param barcode An image of the decoded barcode.
     */
    public void drawResultBitmap(Bitmap barcode) {
        resultBitmap = barcode;
        invalidate();
    }

    public void addPossibleResultPoint(ResultPoint point) {
        possibleResultPoints.add(point);
    }

}
